CN113490571B

CN113490571B - Welding material for high Cr ferrite heat-resistant steel

Info

Publication number: CN113490571B
Application number: CN202080014686.3A
Authority: CN
Inventors: 村西良昌; 小山田宏美; 高内英亮; 宫村刚夫; 难波茂信
Original assignee: Kobe Steel Ltd
Current assignee: Kobe Steel Ltd
Priority date: 2019-02-21
Filing date: 2020-02-13
Publication date: 2023-01-03
Anticipated expiration: 2040-02-13
Also published as: EP3928917A1; CN113490571A; KR20210113346A; WO2020170928A1; JP2020131289A; EP3928917A4; US20220134489A1

Abstract

Provided is a welding material for high-Cr ferritic heat-resistant steel, which can suppress the generation of delta ferrite, which is a soft structure, and thereby can obtain a weld metal having improved toughness and excellent crack resistance and high-temperature strength. A welding material for high-Cr ferritic heat-resistant steel, which contains C, si, mn, S, co, V, nb, W, N and O in predetermined ranges, ni and P in predetermined ranges, and Cr:8.0 to 9.5 mass%, mo:0.02 mass% or more and 0.20 mass% or less, further limiting Cu: less than 0.05 mass%, and the balance being Fe and unavoidable impurities.

Description

Welding material for high Cr ferrite heat-resistant steel

Technical Field

The present invention relates to a welding material suitable for welding high-Cr ferritic heat-resistant steel.

Background

Boilers and turbines for power generation and various heat-resistant pressure-resistant steel pipes are used under high-temperature and high-pressure conditions, and therefore are required to have excellent high-temperature strength, particularly creep performance. High Cr ferritic heat-resistant steel has been developed in response to such a demand, and a welding wire used for the steel has been proposed in a number of ways for various applications.

For example, patent document 1 discloses a welding wire that can obtain a weld metal having excellent high-temperature creep strength (high-temperature strength) and toughness, has excellent welding workability, and can suppress the occurrence of hot cracking in the production of a wire rod.

Prior art documents

Patent document

Patent document 1 Japanese patent application laid-open No. 2004-42116

However, in the above patent document 1, although an appropriate amount of Cu is contained in order to suppress the precipitation of ferrite which adversely affects the toughness of the weld metal, the addition of Cu causes the reduction in the crack resistance of the weld metal, and therefore, there is a demand for the development of a welding material for high-Cr ferritic heat-resistant steel which can obtain a weld metal having excellent high-temperature strength, toughness and crack resistance.

Disclosure of Invention

The present invention has been made in view of the above circumstances, and an object thereof is to provide a welding material for high Cr ferritic heat-resistant steel, which can suppress the generation of δ ferrite, which is a soft structure, and thereby can obtain a weld metal having improved toughness and also excellent crack resistance and high temperature strength.

A welding material for high Cr ferritic heat-resistant steel according to one embodiment of the present invention comprises

C:0.01 to 0.15 mass% inclusive,

Si:0.02 to 0.90 mass%, and,

Mn:0.20 to 1.20 mass% inclusive,

S:0.0005 to 0.015 mass%, and,

Co:0.50 to 5.00 mass% inclusive,

Cr:8.0 to 9.5 mass%,

Mo:0.02 to 0.20 mass%,

V:0.05 to 0.90 mass%, and,

Nb:0.005 to 0.100 mass%,

W: 1.00-5.00 mass%,

N:0.02 to 0.04 mass%, and,

O:0.001 to 0.015 mass%, inclusive,

Cu: less than 0.05 mass%,

Ni:1.20 mass% or less,

P: 0.015% by mass or less of,

the balance being Fe and unavoidable impurities.

Further, the Ni is preferably 0.05 mass% or more and 1.20 mass% or less.

In addition, the welding material for high Cr ferritic heat-resistant steel preferably further contains B: 0.005% by mass or more and 0.015% by mass or less, al:0.015 mass% or less, ti: 0.015% by mass or less.

According to the present invention, it is possible to provide a welding material for high-Cr ferritic heat-resistant steel, which can suppress the generation of δ ferrite, which is a soft structure, and thereby can obtain a weld metal having improved toughness and excellent crack resistance and high-temperature strength.

Detailed Description

Hereinafter, an embodiment (present embodiment) for carrying out the present invention will be described in detail. The present invention is not limited to the embodiments described below, and can be modified and implemented arbitrarily without departing from the scope of the present invention.

Generally, in a weld metal obtained by welding high Cr ferritic heat-resistant steel, δ ferrite, which is a soft structure, is easily generated and reduces the toughness of the weld metal, and therefore, it is effective to increase the toughness of the weld metal by including an element (for example, cu) having an effect of suppressing the generation of δ ferrite in a wire in an appropriate content.

However, the present inventors have focused on the reduction of the crack resistance of the weld metal by adding Cu, and have conducted intensive studies on the type and content of the metal components of the weld material, and as a result, have found that by appropriately adjusting the contents of Mo and Cr, which are the elements forming δ ferrite that affect the reduction of toughness, instead of reducing the content of Cu that contributes to the improvement of toughness but reduces the crack resistance, a weld metal having all of good high-temperature strength, toughness, and crack resistance can be obtained.

The reasons for adding components and the reasons for limiting the composition of the welding material for high Cr ferritic heat-resistant steel of the present embodiment will be described in detail below.

[ composition of welding Material for high Cr ferritic Heat-resistant Steel ]

In the welding material for high Cr ferritic heat-resistant steel of the present embodiment, the following elements are necessarily contained or may be contained as optional components. When the welding material for high Cr ferritic heat-resistant steel of the present embodiment is used as a welding wire (solid wire), the contents of the respective components shown below mean the contents in the total mass of the welding wire.

< C:0.01 to 0.15 mass%

C precipitates as carbide in the weld metal and is an indispensable element for ensuring creep strength.

When the C content is less than 0.01 mass%, the above-mentioned effects cannot be sufficiently obtained. Therefore, the C content in the welding material is 0.01 mass% or more, preferably 0.02 mass% or more, and more preferably 0.03 mass% or more.

On the other hand, since C is also an austenite forming element, if the C content is higher than 0.15 mass%, ac of the weld metal is present ₁ Since the transformation point is lowered, austenite transformation occurs during heat treatment after welding, and as a result, creep strength is lowered and susceptibility to thermal cracking is increased. Therefore, the C content in the welding material is 0.15 mass% or less, preferably 0.13 mass% or less, and more preferably 0.11 mass% or less.

< Si:0.02 mass% or more and 0.90 mass% or less

Si acts as a deoxidizer when the weld metal melts, and is an element contributing to the improvement of impact resistance by reducing the oxygen content in the weld metal. Si also has an effect of reducing the interfacial tension of the molten metal when the weld metal is molten, and reducing weld defects such as lack of fusion and flash.

When the Si content is less than 0.02 mass%, the above-mentioned effects cannot be sufficiently obtained. Therefore, the Si content of the solder material is 0.02 mass% or more, preferably 0.04 mass% or more, and more preferably 0.06 mass% or more.

On the other hand, since Si is a ferrite-generating element, if the Si content is higher than 0.90 mass%, ferrite remains in the weld metal, and the toughness thereof deteriorates. Therefore, the Si content in the solder material is 0.90 mass% or less, preferably 0.70 mass% or less, and more preferably 0.40 mass% or less.

< Mn:0.20 to 1.20 mass% >, respectively

Mn is an essential element from the viewpoint of acting as a deoxidizer when the weld metal melts and ensuring the strength and toughness thereof.

When the Mn content is less than 0.20 mass%, the above effects cannot be sufficiently obtained. Therefore, the Mn content in the welding material is 0.20 mass% or more, preferably 0.30 mass% or more, and more preferably 0.40 mass% or more.

On the other hand, since Mn is an austenite forming element, if the Mn content is more than 1.20 mass%, ac of the weld metal ₁ The transformation point is lowered and the creep strength is lowered. Therefore, the Mn content in the welding material is 1.20 mass% or less, preferably 1.00 mass% or less, and more preferably 0.80 mass% or less.

< S:0.0005 mass% or more and 0.015 mass% or less >

S is an element which lowers the interfacial tension of the molten metal when the weld metal is molten, has an effect of preventing the occurrence of weld defects such as lack of fusion and undercut, and exhibits an effect of improving the welding workability.

If the S content is less than 0.0005 mass%, the above-mentioned effects cannot be sufficiently obtained. Therefore, the S content in the welding material is 0.0005 mass% or more, preferably 0.0007 mass% or more, and more preferably 0.001 mass% or more.

On the other hand, since S is an element that increases the susceptibility to thermal cracking, if the S content is higher than 0.015 mass%, thermal cracking occurs in the weld metal. Therefore, the S content in the welding material is 0.015 mass% or less, preferably 0.012 mass% or less, and more preferably 0.008 mass% or less.

< Co:0.50 to 5.00 mass%

Co is an austenite forming element, and has an effect of suppressing ferrite formation which adversely affects toughness.

When the content of Co is less than 0.50% by mass, the above-mentioned effects cannot be sufficiently obtained. Therefore, the Co content in the welding material is 0.50 mass% or more, preferably 1.00 mass% or more, more preferably 1.50 mass% or more, further preferably 2.00 mass% or more, and particularly preferably 2.50 mass% or more.

On the other hand, if Co is contained excessively, as in Ni, ac is present in the weld metal ₁ The transformation point is lowered and the creep strength is lowered. Therefore, the Co content in the welding material is 5.00 mass% or less, preferably 4.50 mass% or less, more preferably 4.00 mass% or less, and further preferably 3.50 mass% or less.

< Cr:8.0 to 9.5 mass% >, inclusive

Cr is a main alloying element contained in the high Cr ferritic heat-resistant steel targeted for use as the welding material of the present embodiment. Cr is an indispensable element for ensuring the oxidation resistance, corrosion resistance, strength, and the like of the weld metal.

When the Cr content is less than 8.0 mass%, the properties of the weld metal cannot be sufficiently ensured. Therefore, the Cr content in the welding material is 8.0 mass% or more, preferably 8.1 mass% or more, and more preferably 8.2 mass% or more.

On the other hand, cr is a ferrite-forming element, but as described above, in the present embodiment, in order to reduce the Cu content having the ferrite-forming inhibiting effect, the Cr content also needs to be limited to an appropriate amount so as to inhibit the reduction of the toughness of the weld metal. If the Cr content is more than 9.5 mass%, ferrite precipitates in the weld metal and the toughness deteriorates. Therefore, the Cr content in the welding material is 9.5 mass% or less, preferably 9.3 mass% or less, and more preferably 9.2 mass% or less.

< Mo:0.02 mass% or more and 0.20 mass% or less

Mo is a solid-solution strengthening element in steel, and has an effect of improving the strength by dissolving Mo in a weld metal.

When the Mo content is less than 0.02 mass%, the above-described effects cannot be sufficiently obtained. Therefore, the Mo content in the welding material is 0.02 mass% or more, preferably 0.03 mass% or more, and more preferably 0.04 mass% or more.

On the other hand, mo is an element that generates δ ferrite, but as described above, in the present embodiment, in order to reduce the Cu content having the ferrite generation-suppressing effect, the Mo content also needs to be limited to an appropriate amount so as to suppress a decrease in the toughness of the weld metal. If the Mo content is more than 0.20 mass%, the ferrite precipitation toughness in the weld metal deteriorates. Therefore, the Mo content in the welding material is 0.20 mass% or less, preferably 0.15 mass% or less, and more preferably 0.12 mass% or less.

< V:0.05 to 0.90 mass%

V is a precipitation strengthening element in steel, and precipitates as carbonitride in the weld metal, thereby having an effect of improving the strength thereof.

If the V content is less than 0.05 mass%, the above-mentioned effects cannot be sufficiently obtained. Therefore, the V content in the welding material is 0.05 mass% or more, preferably 0.08 mass% or more, and more preferably 0.10 mass% or more.

On the other hand, if the V content is higher than 0.90 mass%, the strength of the weld metal becomes too strong and the toughness deteriorates. Therefore, the V content in the welding material is 0.90 mass% or less, preferably 0.75 mass% or less, more preferably 0.40 mass% or less, and further preferably 0.30 mass% or less.

< Nb:0.005 mass% or more and 0.100 mass% or less

Nb is a precipitation strengthening element in steel, and precipitates as carbonitride in weld metal, thereby having an effect of improving the strength.

If the Nb content is less than 0.005 mass%, the above precipitation strengthening effect cannot be sufficiently obtained. Therefore, the Nb content in the welding material is 0.005 mass% or more, preferably 0.010 mass% or more, and more preferably 0.020 mass% or more.

On the other hand, if the Nb content is higher than 0.100 mass%, the strength of the weld metal becomes too strong, and the toughness deteriorates. Therefore, the Nb content in the weld material is 0.100 mass% or less, preferably 0.09 mass% or less, more preferably 0.08 mass% or less, and still more preferably 0.07 mass% or less.

< W:1.00 mass% or more and 5.00 mass% or less

W is a solid-solution strengthening element in steel, and has an effect of improving the strength by dissolving W in a weld metal.

When the W content is less than 1.00 mass%, the above-mentioned effects cannot be sufficiently obtained. Therefore, the W content in the welding material is 1.00 mass% or more, preferably 1.10 mass% or more, and more preferably 1.20 mass% or more.

On the other hand, since W is also a ferrite-forming element, if it is contained in an amount of more than 5.00 mass%, ferrite is precipitated in the weld metal, and the toughness is deteriorated. Therefore, the W content in the welding material is 5.00 mass% or less, preferably 4.20 mass% or less, and more preferably 3.60 mass% or less.

< N:0.02 to 0.04 mass% > (inclusive)

N is an element that exerts a solid-solution strengthening effect in steel, is bonded to Nb and V to precipitate as a nitride, and contributes to improvement of creep strength of the weld metal. In addition, N is also an element that suppresses the generation of δ ferrite. In the present embodiment, since the Cu content is reduced to suppress a decrease in the crack resistance, it is effective to contain N having the δ ferrite generation suppressing effect in a content of a predetermined amount or more in the welding material.

If the N content is less than 0.02 mass%, the above effects cannot be sufficiently obtained. Therefore, the N content in the welding material is 0.02 mass% or more, preferably 0.021 mass% or more.

On the other hand, N is a strong austenite forming element, and if the content of N is more than 0.04 mass%, ac in the weld metal ₁ The transformation point is lowered and the creep strength is lowered. Therefore, the N content in the welding material is 0.04% by mass or less, preferably 0.038% by mass or less, and more preferably 0.035% by mass or less.

< O:0.001 to 0.015 mass% >, inclusive

O is an element that reduces the interfacial tension of the molten metal when the weld metal is melted, has the effect of preventing the occurrence of weld defects such as lack of fusion and flash, and exhibits the effect of improving the welding workability.

When the content of O is less than 0.001 mass%, the above-mentioned effects cannot be sufficiently obtained. Therefore, the O content in the solder material is 0.001 mass% or more, preferably 0.0015 mass% or more, and more preferably 0.0020 mass% or more.

On the other hand, if the O content is more than 0.015 mass%, the interface tension of the molten metal becomes too low, the bead appearance becomes poor, and a large amount of deoxidation products are generated in the molten metal, and remain in the weld metal, deteriorating the toughness thereof. Therefore, the O content in the weld material is 0.015 mass% or less, preferably 0.014 mass% or less, more preferably 0.013 mass% or less, and particularly preferably 0.012 mass% or less.

< Cu: less than 0.05 mass% (0 mass%) >

Cu is an austenite forming element and has an effect of suppressing the formation of δ ferrite which adversely affects toughness.

If the Cu content is 0.05 mass% or more, the crack resistance of the weld metal deteriorates, and Ac of the weld metal ₁ The transformation point is lowered and the creep strength is lowered. In the present embodiment, since the contents of Mo and Cr that promote the generation of δ ferrite are appropriately adjusted, even if the Cu content is reduced, the crack resistance of the weld metal can be improved while suppressing the reduction in toughness. Therefore, the Cu content in the solder material is less than 0.05 mass%, preferably 0.04 mass% or less, and more preferably 0.03 mass% or less.

< Ni: 1.20% by mass or less (including 0% by mass) >

Ni is an austenite forming element and has an effect of suppressing ferrite formation which adversely affects toughness.

If the Ni content is more than 1.20 mass%, ac in the weld metal ₁ The transformation point is lowered and the creep strength is lowered. In the present embodiment, the contents of Mo and Cr that promote the generation of δ ferrite are adjusted, and therefore, even when Ni is not contained in a predetermined amount or more in the weld material, the desired toughness of the weld metal can be sufficiently ensured. Therefore, the Ni content in the welding material is 1.20 mass% or less, preferably 1.00 mass% or less, and more preferably 0.90 mass% or less.

In order to further improve the toughness of the weld metal, the Ni content in the weld material is preferably 0.05 mass% or more.

< P:0.015 mass% or less (including 0 mass%) >

P is an element that increases thermal cracking, and particularly cracks easily occur in the solidification temperature range and below, which is the process of forming weld metal, and therefore, the content of P needs to be limited. In addition, in the present embodiment, S, which increases the thermal crack sensitivity, is positively added as in P, and therefore, this point is also considered. Therefore, the P content in the welding material is 0.015 mass% or less, preferably 0.010 mass% or less, and more preferably 0.008 mass% or less.

< B:0.005 to 0.015 mass% > (inclusive)

The welding material of the present embodiment preferably further contains, as optional components, B: 0.005% by mass or more and 0.015% by mass or less.

B suppresses coarsening of carbide at crystal grain boundaries in steel, and thus by including B, creep strength of the weld metal can be further improved.

The above-mentioned effects can be obtained if the B content is 0.005% by mass or more. Therefore, B in the welding material is preferably 0.005 mass% or more, and more preferably 0.006 mass% or more.

On the other hand, if the B content is 0.015 mass% or less, the strength of the weld metal becomes excessively strong, and thus the decrease in toughness can be effectively suppressed. Therefore, when B is contained in the welding material, the B content is 0.015 mass% or less, preferably 0.013 mass% or less, and more preferably 0.012 mass%.

< Al:0.015 mass% or less (including 0 mass%) >

When Al is further contained as an optional component in the welding material of the present embodiment, it is preferable to limit Al to 0.015 mass% or less.

Al is an element that acts as a strong deoxidizer when the weld metal melts.

If the Al content is 0.015 mass% or less, the deoxidation becomes excessive, the strength of the weld metal becomes too strong, and the decrease in toughness can be effectively suppressed. Therefore, the Al content in the welding material is 0.015 mass% or less, preferably 0.010 mass% or less, and more preferably 0.008 mass% or less.

< Ti:0.015 mass% or less (including 0 mass%) >

When Ti is further contained as an optional component in the welding material of the present embodiment, it is preferable to limit Ti to 0.015 mass% or less.

Ti is a ferrite-generating element, and precipitates ferrite, which adversely affects toughness, in the weld metal. Further, ti is a strong carbide-forming element, similarly to Nb and V, and is bonded to C to precipitate as a needle-like carbide in the weld metal. The carbide in this form significantly reduces the toughness of the weld metal, and for this reason, it is effective to limit the Ti content, specifically, to 0.015 mass% or less. Therefore, the Ti content in the welding material is 0.015 mass% or less, preferably 0.010 mass% or less, and more preferably 0.008 mass% or less.

< margin >

The balance of the welding material in the present embodiment is Fe and unavoidable impurities. Examples of the inevitable impurities include Li, mg, and Zr.

In the welding material of the present embodiment, the Fe content is preferably 75 mass% or more, and more preferably 78 mass% or more, with respect to the total mass of the welding material.

[ concerning welding materials ]

The welding material for high Cr ferritic heat-resistant steel of the present embodiment can be processed into a welding rod, a filler wire for gas tungsten arc welding, a core wire of a welding rod for arc welding, or the like by a known production method. The welding material according to the present embodiment can be used for any of TIG welding, MAG welding, and submerged arc welding when welding high Cr ferritic heat-resistant steel.

In addition, when welding is performed using the welding material of the present embodiment, the effects of the present embodiment described above can be obtained as long as the content of each component in the obtained weld metal is within the range of the content of each element in the welding material of the present embodiment.

Examples

The present invention will be described in more detail below by way of examples of the invention and comparative examples, but the present invention is not limited thereto.

[ production of welding wire ]

Steel ingots having the composition shown in table 1 below (the balance being Fe and unavoidable impurities) were melted, hot rolled and cold drawn to produce wires having a diameter of 1.6 mm. The contents of the chemical components shown in table 1 are the contents (mass%) of the total mass of the wire.

[ welding ]

Next, the mild steel sheet was subjected to barrier layer build-up Welding using the above-described Welding wire, and after the groove was machined, automatic Gas Tungsten Arc Welding (GTAW: gas Tungsten Arc Welding) was performed in the groove. Thereafter, post-welding Heat Treatment (PWHT: post Weld Heat Treatment) is performed at a temperature of 740 to 760 ℃. The welding conditions are shown below.

(welding conditions)

Plate thickness of base material: 12mm

Bevel angle, shape: 45 degree and V type

Root spacing: 6.5mm

Diameter of welding wire: 1.6mm

Current: 220-240A/230A

Voltage: 10-12V/11V

Welding speed: 8-10 cm/min

Type and flow rate of gas: 100% Ar, 25 l/min

Welding wire feeding amount: 8g/min

Preheating and interlayer temperature: 250-300 DEG C

The lamination method comprises the following steps: 6-7 layers of 9-13 channels

[ evaluation ]

The weld metal after PWHT at the temperature and time shown in table 2 below was subjected to the following various tests to evaluate the high temperature strength, toughness, and crack resistance of the weld metal, and the metal structure was observed. The evaluation results of the respective tests are shown together in table 2 below.

< high temperature Strength >

For the weld metal after PWHT, a high temperature tensile test at 650 ℃ was carried out in accordance with JIS Z3111, and 0.2% yield strength (0.2% YS) was measured. The obtained value was 280MPa or more, and evaluated as follows: a (Excellent), 250MPa or more and less than 280MPa, evaluated: b (good), less than 250MPa, evaluated: c (bad).

< toughness >

The weld metal after PWHT was subjected to a Charpy impact test at 20 ℃ in accordance with JIS Z2242 to measure the absorption work vE (J) and evaluate the toughness. Also, the absorption work measured was 60J or more, and evaluated: a (excellent), 27J or more and less than 60J, evaluation: b (good), less than 27J, evaluation: c (bad).

< crack resistance >

The weld metal after PWHT was evaluated for crack resistance by observing the microstructure to confirm the presence or absence of cracks. Further, the microstructure was observed, and the sample was judged to be non-cracked.

< Metal texture >

For the weld metal after PWHT, the area ratio of δ ferrite was measured at the original portion of the final weld bead in the microstructure observation, and the soundness of the metal structure was evaluated. If the area ratio of the delta ferrite is less than 2%, the delta ferrite is judged to be absent, and the quality is qualified. On the other hand, the area ratio of δ ferrite was 2% or more, and it was judged that δ ferrite was present, and thus it was not acceptable.

[ Table 1]

[ Table 2]

As shown in tables 1 and 2, in inventive examples 1 to 6, since the content of all chemical components in the welding material (wire) is within the range of the present invention, the welding using these wires suppressed the generation of δ ferrite, and it was possible to obtain weld metals excellent in all of toughness, crack resistance, and high-temperature strength.

On the other hand, in comparative examples 1, 3 and 4, since the Mo content and the N content in the wire were lower than the lower limit of the range of the present invention, the high temperature strength was lowered compared to the inventive examples.

In comparative example 2, the Mo content and the N content in the wire were lower than the lower limits of the ranges of the present invention, and the B content for improving the high temperature strength was higher than the upper limit of the preferable range of the present invention, so that the toughness was lowered while the lowering of the high temperature strength was suppressed.

In comparative examples 5 to 7, since the Mo content in the wire is higher than the upper limit of the range of the present invention, δ ferrite is precipitated in the weld metal, the toughness is deteriorated, and the crack resistance is lowered.

As described in detail above, according to the present invention, it is possible to provide a welding material for high Cr ferritic heat-resistant steel, which can suppress the generation of δ ferrite, which is a soft structure, and thereby can obtain a weld metal having improved toughness and excellent crack resistance and high temperature strength.

While various embodiments have been described above, it is needless to say that the present invention is not limited to such examples. It is obvious to the practitioner that various modifications and alterations can be made within the scope of the claims and that these modifications are also regarded as falling within the technical scope of the present invention. Further, the respective constituent elements in the above embodiments may be arbitrarily combined without departing from the scope of the invention.

The present application is based on japanese patent application No. 21/2/2019 (japanese patent application No. 2019-029843), the contents of which are incorporated herein by reference.

Claims

1. A welding material for high Cr ferritic heat-resistant steel, characterized by containing

C:0.01 to 0.15 mass% inclusive,

Si:0.02 to 0.90 mass%,

Mn:0.20 to 1.20 mass%, and,

S:0.0005 to 0.015 mass%, and,

Co:0.50 to 5.00 mass% inclusive,

Cr:8.0 to 9.5 mass%,

Mo:0.02 to 0.20 mass%,

V:0.05 to 0.90 mass%, and,

Nb:0.005 to 0.100 mass%,

W: 1.00-5.00 mass%,

N:0.02 to 0.04 mass%, and,

O:0.001 to 0.015 mass% inclusive,

B: 0.007-0.015 wt.% and below

Cu: less than 0.05 mass%,

Ni:1.20 mass% or less,

P: less than 0.015 mass%,

The balance being Fe and unavoidable impurities.

2. The welding material for high-Cr ferritic heat-resistant steel according to claim 1, wherein the Ni is 0.05 mass% or more and 1.20 mass% or less.

3. The welding material for high-Cr ferritic heat-resistant steel according to claim 1 or 2, further comprising

Al: less than 0.015 mass%,

Ti: 0.015% by mass or less.